Khwarazmian dynasty

The date of the founding of the Khwarazmian dynasty remains debatable. During a revolt in 1017, Khwarezmian rebels murdered Abu'l-Abbas Ma'mun and his wife, Hurra-ji, sister of the Ghaznavid sultan Mahmud.[18] In response, Mahmud invaded and occupied the region of Khwarezm, which included Nasa and the ribat of Farawa.[19] As a result, Khwarezm became a province of the Ghaznavid Empire from 1017 to 1034. In 1077, the governorship of the province, which since 1042/1043 belonged to the Seljuqs, fell into the hands of Anush Tigin Gharchai, a former Turkic slave of the Seljuq sultan. In 1141, the Seljuq Sultan Ahmed Sanjar was defeated by the Qara Khitai at the battle of Qatwan, and Anush Tigin's grandson Ala ad-Din Atsiz became a vassal to Yelü Dashi of the Qara Khitan.[20]

Sultan Ahmed Sanjar died in 1156. As the Seljuk state fell into chaos, the Khwarezm-Shahs expanded their territories southward. In 1194, the last Sultan of the Great Seljuq Empire, Toghrul III, was defeated and killed by the Khwarezm ruler Ala ad-Din Tekish, who conquered parts of Khorasan and western Iran. In 1200, Tekish died and was succeeded by his son, Ala ad-Din Muhammad, who initiated a conflict with the Ghurids and was defeated by them at Amu Darya (1204).[21] Following the sack of Khwarizm, Muhammad appealed for aid from his suzerain, the Qara Khitai who sent him an army.[22] With this reinforcement, Muhammad won a victory over the Ghurids at Hezarasp (1204) and forced them out of Khwarizm.

Ala ad-Din Muhammad's alliance with his suzerain was short-lived. He again initiated a conflict, this time with the aid of the Kara-Khanids, and defeated a Qara-Khitai army at Talas (1210),[23] but allowed Samarkand (1210) to be occupied by the Qara-Khitai.[24] He overthrew the Karakhanids (1212)[25] and Ghurids (1215). In 1212, he shifted his capital from Gurganj to Samarkand. Thus incorporating nearly the whole of Transoxania and present-day Afghanistan into his empire, which after further conquests in western Persia (by 1217) stretched from the Syr Darya to the Zagros Mountains, and from the northern parts of the Hindu Kush to the Caspian Sea. By 1218, the empire had a population of 5 million people.[26]

In 1218, Genghis Khan sent a trade mission to the state, but at the town of Otrar the governor, suspecting the Khan's ambassadors to be spies, confiscated their goods and executed them. Genghis Khan demanded reparations, which the Shah refused to pay. Genghis retaliated with a force of 200,000 men, launching a multi-pronged invasion. In February 1220 the Mongolian army crossed the Syr Darya. The Mongols stormed Bukhara, Gurganj and the Khwarezmid capital Samarkand. The Shah fled and died some weeks later on an island in the Caspian Sea.

The son of Ala ad-Din Muhammad, Jalal ad-Din Mingburnu, became the new Sultan (he rejected the title Shah). He attempted to flee to India, but the Mongols caught up with him before he got there, and he was defeated at the Battle of Indus. He escaped and sought asylum in the Sultanate of Delhi. Iltumish however denied this to him in deference to the relationship with the Abbasid caliphs. Returning to Persia, he gathered an army and re-established a kingdom. He never consolidated his power, however, spending the rest of his days struggling against the Mongols, the Seljuks of Rum, and pretenders to his own throne. He lost his power over Persia in a battle against the Mongols in the Alborz Mountains. Escaping to the Caucasus, he captured Azerbaijan in 1225, setting up his capital at Tabriz. In 1226 he attacked Georgia and sacked Tbilisi. Following on through the Armenian highlands he clashed with the Ayyubids, capturing the town Ahlat along the western shores of the Lake Van, who sought the aid of the Seljuk Sultanate of Rûm. Sultan Kayqubad I defeated him at Arzinjan on the Upper Euphrates at the Battle of Yassıçemen in 1230. He escaped to Diyarbakir, while the Mongols conquered Azerbaijan in the ensuing confusion. He was murdered in 1231 by Kurdish highwaymen.[27]

Eurasia c. 1200, on the eve of the Mongol invasions.

Though the Mongols had destroyed the Khwarezmian Empire in 1220, many Khwarezmians survived by working as mercenaries in northern Iraq. Sultan Jalal ad-Din's followers remained loyal to him even after his death in 1231, and raided the Seljuk lands of Jazira and Syria for the next several years, calling themselves the Khwarezmiyya. Ayyubid Sultan as-Salih Ayyub, in Egypt, later hired their services against his uncle as-Salih Ismail. The Khwarezmiyya, heading south from Iraq towards Egypt, invaded Crusader-held Jerusalem along the way, on 11 July 1244. The city's citadel, the Tower of David, surrendered on 23 August, and the Christian population of the city was expelled. This triggered a call from Europe for the Seventh Crusade, but the Crusaders would never again be successful in retaking Jerusalem. After being conquered by the Khwarezmian forces, the city stayed under Muslim control until 1917, when it was taken from the Ottomans by the British.

After taking Jerusalem, the Khwarezmian forces continued south, and on 17 October fought on the side of the Ayyubids at the Battle of La Forbie, as the Crusaders used to call Harbiyah, a village northeast of Gaza, destroying the remains of the Crusader army there, with some 1,200 knights killed. It was the largest battle involving the Crusaders since the Battle of the Horns of Hattin in 1187.[28]

The remaining Muslim Khwarezmians served in Egypt as Mamluk mercenaries until they were finally beaten by al-Mansur Ibrahim some years later.

Khwarezmi war captives assimilated into the Mongols, forming the modern Mongolian clan Sartuul.

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  Mausoleum of Khwarazm Shah, Il-Arslan, Köneürgench, Turkmenistan
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  Mausoleum of Khwarazm Shah Tekish, Köneürgench, Turkmenistan
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  The fortress of Guldursun-Kala was last occupied by Muhammad II of Khwarazm (1169, 1200-20), before it fell to the Mongol conquest of the Khwarazmian Empire.

• Full list of Persian Kingdoms
• Khwarezmia
• List of Sunni Muslim dynasties

• M. Ismail Marcinkowski, Persian Historiography and Geography: Bertold Spuler on Major Works Produced in Iran, the Caucasus, Central Asia, India and Early Ottoman Turkey, with a foreword by Professor Clifford Edmund Bosworth, member of the British Academy, Singapore: Pustaka Nasional, 2003, ISBN 9971-77-488-7.